학술논문

Measurement of the neutrino-oxygen neutral-current quasielastic cross section using atmospheric neutrinos at Super-Kamiokande
Document Type
article
Source
Physical Review D. 99(3)
Subject
Nuclear and Plasma Physics
Particle and High Energy Physics
Physical Sciences
hep-ex
Astronomical and Space Sciences
Atomic
Molecular
Nuclear
Particle and Plasma Physics
Quantum Physics
Nuclear & Particles Physics
Mathematical physics
Astronomical sciences
Particle and high energy physics
Language
Abstract
Neutral current (NC) interactions of atmospheric neutrinos on oxygen form one of the major backgrounds in the search for supernova relic neutrinos with water-based Cherenkov detectors. The NC channel is dominated by neutrino quasielastic (NCQE) scattering off nucleons inside O16 nuclei. In this paper we report the first measurement of NCQE cross section using atmospheric neutrinos at Super-Kamiokande (SK). The measurement used 2,778 live days of SK-IV data with a fiducial volume of 22.5 kiloton water. Within the visible energy window of 7.5-29.5 MeV, we observed 117 events compared to the expected 71.9 NCQE signal and 53.1 background events. Weighted by the atmospheric neutrino spectrum from 160 MeV to 10 GeV, the flux averaged NCQE cross section is measured to be (1.01±0.17(stat.)-0.30+0.78(sys.))×10-38 cm2.